Thin film transistor array panel and fabrication

ABSTRACT

The present invention provides a manufacturing method of a thin film transistor array panel, which includes forming a gate line on a substrate; forming a gate insulating layer, a semiconductor layer, and an ohmic contact on the gate line; forming a first conducting film including Mo, a second conducting film including Al, and a third conducting film including Mo on the ohmic contact; forming a first photoresist pattern on the third conducting film; etching the first, second, and third conducting films, the ohmic contact, and the semiconductor layer using the first photoresist pattern as a mask; removing the first photoresist pattern by a predetermined thickness to form a second photoresist pattern; etching the first, second, and third conducting films using the second photoresist pattern as a mask to expose a portion of the ohmic contact; and etching the exposed ohmic contact using a Cl-containing gas and a F-containing gas.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application is a Continuation of U.S. application Ser. No.12/099,718, filed Apr. 8, 2008, which is a Divisional of U.S.application Ser. No. 11/486,330, filed Jul. 12, 2007, now U.S. Pat. No.7,371,621, issued on May 13, 2008, which applications claim priority toand the benefit of Korean Patent Application No. 10-2005-0062730 filedin the Korean Intellectual Property Office on Jul. 12, 2005, thecontents of which are hereby incorporated by reference herein in theirentirety.

FIELD OF THE INVENTION

The present invention relates to a thin film transistor array panel anda manufacturing method thereof.

DESCRIPTION OF THE RELATED ART

Liquid crystal displays (LCDs) are one of the most widely used flatpanel displays. An LCD includes a liquid crystal (LC) layer interposedbetween two panels wherein one panel (referred to as “a thin filmtransistor array panel”) has a plurality of pixel electrodes in a matrixand the other (referred to as “a common electrode panel”), has a commonelectrode covering the entire surface of the panel. The LCD displaysimages by applying voltages to the field-generating electrodes togenerate an electric field in the LC layer that determines theorientation of the LC molecules in the LC layer to adjust thepolarization of incident light. Thin film transistors (TFTs) havingthree terminals are connected to the pixel electrodes. Gate linestransmit signals for controlling the thin film transistors and the datalines transmit voltages applied to the pixel electrodes are formed on athin film transistor array panel. The thin film transistor array panelincludes a plurality of thin films having conducting films such as thegate lines and the data lines, a semiconductor layer, and an insulatinglayer. The respective thin films are patterned using separate masks.

The various patterning steps such as applying the photolithographicmask, exposing to light, developing, and cleansing are repeated for eachseparate mask thereby making the manufacturing process costly and timeconsuming. Therefore, it is preferable to decrease the number ofrequired masks. However, when the metal layer for the data lines and thesemiconductor are etched using the same mask, some of the semiconductorlayer is left on the entire surface under the etched metal layer causingafterimages because of light leakage from the semiconductor area.

SUMMARY OF THE INVENTION

In accordance with the invention, the after image problem is eliminatedeven though the metal patterns for the multi-layered data linesstructured of an Al film and an underlying Mo film and the intrinsicsemiconductor are etched using the same photoresist pattern. Thediffusion of Mo into the semiconductors and the splitting of impuritiesfrom the lower Al film are prevented from polluting the semiconductorchannel during wet etching. In forming the channel areas, the flow ratioof the chlorine-containing gas and the fluorine-containing gas iscontrolled within a predetermined ratio.

BRIEF DESCRIPTION OF THE DRAWING

The foregoing objects and features of the present invention may becomemore apparent from a reading of the ensuing description together withthe drawing, in which:

FIG. 1 is layout view of a TFT array panel according to an embodiment ofthe present invention;

FIGS. 2 and 3 are sectional views of the TFT array panel shown in FIG. 1taken along the lines II-II′ and III-III′;

FIGS. 4, 15, and 18 are layout views of the TFT array panel inintermediate steps of a manufacturing method thereof according to anembodiment of the present invention;

FIGS. 5 and 6 are sectional views of the TFT array panel shown in FIG. 4taken along the lines V-V′ and VI-VI′;

FIGS. 7 to 14 are sectional views sequentially showing a manufacturingmethod of a TFT array panel according to an embodiment of the presentinvention;

FIGS. 16 and 17 are sectional views of the TFT array panel shown in FIG.15 taken along the lines XVI-XVI′ and XVII-XVII′;

FIGS. 19 and 20 are sectional views of the TFT array panel shown in FIG.18 taken along the lines XIX-XIX′ and XX-XX′; and

FIGS. 21A and 21B are graphs indicating characteristics of a TFT inaccordance with a supplied amount of Cl.

DETAILED DESCRIPTION

An exemplary embodiment of the present invention will hereinafter bedescribed in detail with reference to the accompanying drawings. Asthose skilled in the art would realize, the described embodiments may bemodified in various different ways, all without departing from thespirit or scope of the present invention. In the drawings, the thicknessof layers, films, panels, regions, etc., are exaggerated for clarity.Like reference numerals designate like elements throughout thespecification. It will be understood that when an element such as alayer, region, or substrate is referred to as being “on” anotherelement, it can be directly on the other element or intervening elementsmay also be present. In contrast, when an element is referred to asbeing “directly on” another element, there are no intervening elementspresent.

A TFT array panel according to an embodiment of the present inventionwill be described in detail with reference to FIGS. 1 to 3. FIG. 1 islayout view of a TFT array panel according to an embodiment of thepresent invention, and FIGS. 2 and 3 are sectional views of the TFTarray panel shown in FIG. 1 taken along the lines II-II′ and III-III′.

A plurality of gate lines 121 and a plurality of storage electrode lines131 are formed on an insulating substrate 110 made of a material such astransparent glass or plastic. Gate lines 121 transmit gate signals andextend substantially in a transverse direction. Each of gate lines 121includes a plurality of gate electrodes 124 projecting downward, and anend portion 129 having a large area for contact with another layer or anexternal driving circuit. A gate driving circuit (not shown) generatesthe gate signals and may be mounted on a flexible printed circuit (FPC)film (not shown), which may be attached to the substrate 110, directlymounted on the substrate 110, or integrated into the substrate 110. Gatelines 121 may be connected to a driving circuit that may be integratedinto the substrate 110.

Storage electrodes 131 are supplied with a predetermined voltage, andeach of storage electrode lines 131 includes a stem extendingsubstantially parallel to gate lines 121 and a plurality of pairs ofstorage electrodes 133 a and 133 b branched from the stem. Each ofstorage electrode lines 131 is disposed between two adjacent gate lines121, and the stem is close to a lower one of the two adjacent gate lines121. Each of storage electrodes 133 a and 133 b has a fixed end portionconnected to the stem and a free end portion disposed opposite thereto.The fixed end portion of storage electrode 133 b has a large area, andthe free end portion thereof is bifurcated into a linear branch and acurved branch. However, storage electrode lines 131 may have variousshapes and arrangements.

Gate lines 121 and storage electrode lines 131 include lower films 124p, 131 p, 133 ap, and 133 bp including an Al-containing metal such as Alor a Al alloy, and upper films 124 q, 131 q, 133 aq, and 133 bqincluding an Mo-containing metal such as Mo or a Mo alloy. Al—Nd, whichNd is added to Al in a predetermined amount may be used as theAl-containing metal. The thickness of the lower films 124 p, 131 p, 133ap, and 133 bp may be about 100 Å to 5000 Å, and the thickness of theupper films 124 q, 131 q, 133 aq, and 133 bq may be about 50 Å to 2000Å.

In FIGS. 2 and 3, for gate electrodes 124 and storage electrode lines131, the lower and upper films thereof are denoted by the additionalcharacters p and q, respectively. The lateral sides of gate lines 121and storage electrode lines 131 are inclined relative to a surface ofthe substrate 110, and the inclination angles thereof range about 30-80degrees. A gate insulating layer 140, preferably made of silicon nitride(SiNx) or silicon oxide (SiOx), is formed on gate lines 121 and storageelectrode lines 131. A plurality of semiconductor stripes 151 preferablymade of hydrogenated amorphous silicon (abbreviated to “a-Si”) orpolysilicon are formed on gate insulating layer 140. Each of thesemiconductor stripes 151 extends substantially in the longitudinaldirection and includes a plurality of projections 154 branched outtoward gate electrodes 124. The semiconductor stripes 151 become widenear gate lines 121 and storage electrode lines 131 such that thesemiconductor stripes 151 cover large areas of gate lines 121 andstorage electrode lines 131.

A plurality of ohmic contact stripes and islands 161 and 165 are formedon the semiconductor stripes 151. The ohmic contact stripes and islands161 and 165 are preferably made of n+hydrogenated a-Si heavily dopedwith an n-type impurity such as phosphorous P, or they may be made ofsilicide. Each ohmic contact stripe 161 includes a plurality ofprojections 163, and the projections 163 and the ohmic contact islands165 are located in pairs on the projections 154 of the semiconductorstripes 151. The lateral sides of the semiconductor stripes 151 and theohmic contacts 161 and 165 are inclined relative to the surface of thesubstrate 110, and the inclination angles thereof are preferably in arange of about 30-80 degrees.

A plurality of data lines 171 and a plurality of drain electrodes 175are formed on the ohmic contacts 161 and 165 and gate insulating layer140. Data lines 171 transmit data signals and extend substantially inthe longitudinal direction to intersect gate lines 121. Each data line171 also intersects storage electrode lines 131 and runs betweenadjacent pairs of storage electrodes 133 a and 133 b. Each data line 171includes a plurality of source electrodes 173 projecting toward gateelectrodes 124 and an end portion 179 having a large area for contactwith another layer or an external driving circuit. A data drivingcircuit (not shown) for generating data signals may be mounted on an FPCfilm (not shown), which may be attached to the substrate 110, directlymounted on the substrate 110, or integrated into the substrate 110. Datalines 171 may extend to be connected to a driving circuit that may beintegrated into the substrate 110.

Drain electrodes 175 are separated from data lines 171 and are disposedopposite source electrodes 173 with respect to gate electrodes 124. Eachof drain electrodes 175 includes a wide end portion and a narrow endportion. The wide end overlaps storage electrode line 131 and the narrowend is partly enclosed by source electrode 173.

Gate electrode 124, source electrode 173, and drain electrode 175 alongwith projection 154 of semiconductor stripe 151 form a TFT having achannel in projection 154 between source electrode 173 and drainelectrode 175.

Data lines 171 and drain electrodes 175 have a triple-layered structureincluding a lower film 171 p and 175 p, an intermediate film 171 q and175 q, and an upper film 171 r and 175 r. The lower film 171 p and 175 pis preferably made of Mo or a Mo-containing metal of a Mo alloy such asMoN, MoNb, MoV, MoTi, and MoW, the intermediate film 171 q and 175 q ispreferably made of a low resistivity metal of Al or an Al-containingmetal such as AlNd, and the upper film 171 r and 175 r is made of Mo ora Mo-containing metal of a Mo alloy such as MoN, MoNb, MoV, MoTi, andMoW having a good contact characteristic with ITO or IZO.

In FIGS. 2 and 3, the lower, intermediate, and upper films of sourceelectrodes 173 and of end portions 179, are denoted by additionalcharacters p, q, and r, respectively. Data lines 171 and drainelectrodes 175 have edge profiles inclined at an angle of about 30-80degrees.

Ohmic contacts 161 and 165 are interposed only between the underlyingsemiconductor stripes 151 and the overlying conductors 171 and 175 toreduce contact resistance therebetween.

Semiconductor stripes 151 have almost the same planar shapes as datalines 171 and drain electrodes 175 as well as the underlying ohmiccontacts 161 and 165, except for the projections 154 on which TFTs areformed. That is, the semiconductor stripes 151 are formed under datalines 171 and drain electrodes 175 and the underlying ohmic contacts161, 163, and 165, and include some exposed portions that are notcovered with data lines 171 and drain electrodes 175, such as theportions located between the source electrodes 173 and drain electrodes175.

A passivation layer 180 is formed on data lines 171, drain electrodes175, and the exposed portions of the semiconductor stripes 151.Passivation layer 180 may be made of inorganic insulators such assilicon nitride and silicon oxide, an organic insulator, or a lowdielectric insulator, and it may have a flat top surface. The organicinsulator and the low dielectric insulator may have a dielectricconstant of less than about 4.0. Examples of the low dielectricinsulator include a-Si:C:O and a-Si:O:F formed by plasma enhancedchemical vapor deposition (PECVD). The organic insulator may exhibitphotosensitivity. Passivation layer 180 may include a lower film of aninorganic insulator and an upper film of an organic insulator, such thatit takes on the excellent insulating characteristics of the organicinsulator while preventing the exposed portions of the semiconductorstripes 151 from being damaged by the organic insulator.

Passivation layer 180 has a plurality of contact holes 182 and 185exposing the end portions 179 of data lines 171 and drain electrodes175, respectively. Passivation layer 180 and gate insulating layer 140have a plurality of contact holes 181 exposing the end portions 129 ofgate lines 121 and a plurality of contact holes 184 exposing portionsnear the fixed end portions of storage electrode 133 a and 133 b orportions of the free end portions of storage electrode lines 131.

A plurality of pixel electrodes 191, a plurality of overpasses 83, and aplurality of contact assistants 81 and 82 are formed on the passivationlayer 180. They are preferably made of a transparent conductor such asITO or IZO or a reflective conductor such as Ag, Al, or alloys thereof.Pixel electrodes 191 are physically and electrically connected to drainelectrodes 175 through the contact holes 185 such that pixel electrodes191 receive data voltages from drain electrodes 175. Pixel electrodes191 supplied with data voltages generate electric fields in cooperationwith a common electrode (not shown) of an opposing display panel (notshown) supplied with a common voltage, This voltage determines theorientation of the liquid crystal molecules (not shown) of the liquidcrystal layer (not shown) disposed between the two electrodes. A pixelelectrode 191 and the common electrode form a capacitor referred to asthe “liquid crystal capacitor” which stores applied voltages after theTFT is turned off.

Pixel electrode 191 overlaps storage electrode line 131 includingstorage electrodes 133 a and 133 b. Pixel electrode 191, drain electrode175 connected thereto, and storage electrode line 131 form an additionalcapacitor referred to as a “storage capacitor,” which enhances thecharge storing capacity of the liquid crystal capacitor.

Contact assistants 81 and 82 are connected to end portions 129 of gatelines 121 and end portions 179 of data lines 171 through contact holes181 and 182, respectively. Contact assistants 81 and 82 protect endportions 129 and 179 and enhance the adhesion between the end portionsand external devices.

Overpasses 84 cross over gate lines 121 and are connected to the exposedportions of storage electrode lines 131 and the exposed end portions ofthe free end portions of storage electrodes 133 b through a pair ofcontact holes 184, respectively, which are disposed opposite each otherwith respect to gate lines 121. Storage electrode lines 131 includingstorage electrodes 133 a and 133 b along with the overpasses 84 can beused for repairing defects in gate lines 121, data lines 171, or theTFTs.

The method of manufacturing the TFT array panel shown in FIGS. 1 to 3according to an embodiment of the present invention will be described indetail with reference to FIGS. 4 to 20 as well as FIGS. 1 to 3. As shownin FIGS. 4 to 6, a lower film of AlNd and an upper film of aMo-containing metal are sequentially deposited on insulating substrate110 made of a material such as transparent glass or plastic.

Next, a plurality of gate lines 121 including gate electrodes 124 andend portions 129 and a plurality of storage electrode lines 131including storage electrodes 133 a and 133 b are formed by wet etchingthe upper and lower films.

As shown in FIGS. 7 and 8, a gate insulating layer 140 made of amaterial such as SiNx, an intrinsic a-Si layer 150, and an extrinsica-Si layer 160 are sequentially deposited on gate lines 121 and storageelectrode lines 131 by PECVD. The intrinsic a-Si layer 150 is made ofhydrogenated amorphous silicon, and the extrinsic a-Si layer 160 is madeof n+hydrogenated a-Si heavily doped with an n-type impurity such asphosphorous P.

Sequentially, a lower Mo film 170 p made of a Mo-containing metal, an Alintermediate film 170 q made of an Al-containing film, and a upper Mofilm 170 r made of a Mo-containing film 170 r are sequentially depositedby sputtering such that a data metal layer 170 is formed.

A photoresist is coated on the upper Mo film 170 r. The photoresist isexposed to light through an exposure mask (not shown), and the developedphotoresist has a position dependent thickness as shown in FIGS. 9 and10. The developed photoresist includes a plurality of first to thirdportions 54 and 52. The first portions 54 are located on channel areasB, and the second portions 52 are located on data line areas A. Noreference numeral is assigned to the third portions located on theremaining areas C since they have substantially zero thickness. Thethickness ratio of the first portions 54 to the second portions 52 isadjusted depending upon the process conditions in the subsequent processsteps. It is preferable that the thickness of the first portions 54 isequal to or less than half of the thickness of the second portions 52.

The position-dependent thickness of the photoresist is obtained byseveral techniques, for example by providing translucent areas on theexposure mask as well as transparent areas and light blocking opaqueareas. The translucent areas may have a slit pattern, a lattice pattern,a thin film(s) with intermediate transmittance, or an intermediatethickness. When using a slit pattern, it is preferable that the width ofthe slits or the distance between the slits be smaller than theresolution of a light projector used for the photolithography. Anotherexample is to use reflowable photoresist. In detail, once a photoresistpattern made of a reflowable material is formed by using a normalexposure mask with only transparent areas and opaque areas, it issubject to a reflow process to flow onto areas without the photoresist,thereby forming thin portions.

Referring to FIGS. 11 and 12, the exposed portions of data metal layer170 on the remaining areas C are etched by wet etching such thatportions 174 and 179 of data metal layer 170 are left on data areas Aand channel areas B. Next, exposed portions of the extrinsic a-Si layer160 and the underlying portions of the intrinsic semiconductor layer 150on the remaining areas C are removed by dry etching such that thesemiconductor patterns 161, 164, 151, and 154 are formed.

Next, the photoresist patterns 54 on the channel areas B are removed byan etch back process. At this time, the thickness of the photoresistpattern 52 reduces by predetermined amount.

Referring to FIGS. 13 and 14, using the photoresist pattern 52 as amask, the exposed data metal patterns 174 are wet-etched to separatedata metal patterns 174 into source electrodes 173 and drain electrodes175, and expose the extrinsic semiconductor patterns 164 on the channelareas between the source electrodes 173 and drain electrodes 175.

The extrinsic semiconductor patterns 164 on the channel areas aredry-etched using the photoresist pattern 52 as a mask. At this time, achlorine-containing gas or a fluorine-containing gas is used for dryetching. The chlorine-containing gas may be a gas containing chlorineatoms Cl such as Cl₂, HCl, BCl₃, CCl₄, or SiCl₂H₂. Thefluorine-containing gas may be supplied by predetermined amount toimprove characteristics of the underlying intrinsic semiconductors 154and may contain fluorine atoms such as SF₆ or CF₄. An inert gas such asH₂ and He may be supplied along with the chlorine-containing gas and thefluorine-containing gas for the dry etching. Dry etching is performedunder a pressure of about 100 to 800 mT.

When HCl+SF₆+He is used as an etching gas, a flow ratio of SF₆:HCl ispreferably about 1:4 to 1:10. When Cl₂+SF₆+He is used as an etching gas,the flow ratio of SF₆:HCl is preferably about 1:1 to 1:10. The flowratio has a range to improve characteristics of the TFTs, but not toinfluence the dry etching. In particular, since Cl₂ has a bonddissociation energy smaller than that of the HCl, radical and ionemission easily occurs, and a gas amount exhausted for the dry etchingdecreases. The chlorine-containing gas improves the characteristics ofthe TFTs.

In detail, when data metal patterns 171, 174, and 179 and intrinsicsemiconductor 150 are etched using the same photoresist patterns, datalines 171 including the source electrodes 173 and the end portions 179and the semiconductors 151 including the projections 154 havesubstantially the same planar shapes. Areas of the semiconductors 151exposed to light from a light source such as a backlight unit becomewide and increase photo leakage current. The photo leakage currentsignificantly influences data lines 171 having a multi-layered structureof an Al film and an underlying Mo film. That is, the Mo diffuses intosemiconductors 151 and impurities split from the lower Al film pollutethe semiconductor channel in the wet etching. Accordingly, the TFTcharacteristics of off-current, threshold voltage are degraded andafterimages, occur.

However, in etching the extrinsic semiconductor patterns 164, that is,in forming the channel areas, the flow ratio of the chlorine-containinggas and the fluorine-containing gas is controlled within thepredetermined ratios, to decrease the above disadvantages. In formingthe channel areas, when the chlorine-containing gas within the regionsis used, the remaining Cl atoms remain in the projections 154 of thesemiconductors 151.

TABLE 1 shows test examples indicating that the afterimages decreasewhen the flow amount of the chlorine-containing gas is different fromthat of the fluorine-containing gas in forming the channel areas. Ineach of the test examples, pressure, power, and He supply amount were170 mT, 3400 W, and 900 sccm, respectively. Furthermore, in each of thetest examples, a flow amount of the SF₆ was fixed as 150 sccm, and aflow amount of the Cl₂ or HCl was controlled based on the flow amount ofthe SF₆ from about 0 to the predetermined ratio, to supply anappropriate flow amount.

The afterimage characteristic was tested as below. First, display panelsfor a test were prepared, which include channel areas formed by anetching gas having the respective corresponding flow ratio. Each of thedisplay panels included a plurality of pixels arranged in a matrixthereon. Data voltages representing one of intermediate grays between awhite gray and a black gray were applied to the display panels, tomeasure luminance of display screens of the display panels,respectively. Next, data voltages with respect to the black gray and thewhite gray were alternately applied in a row direction and a columndirection to represent the gray and the white gray for about ten hours.Sequentially, after data voltages to the intermediate grays were appliedagain, luminance of the display screen was detected, to measureafterimage degree.

TABLE 1 After After image image Etching Flow ratio improve- Etching Flowratio improve- char- (SF₆:Cl₂) ment characteristic (SF₆:HCl) mentacteristic 1:0 X 1:0 X 1:0.3 X 1:1.12 X 1:0.7 Δ 1:3 X 1:1 ◯ 1:3.5 1:4 ◯1:4 ◯ 1:6 1:6.5 ◯ 1:8.2 1:9 1:9.4 ◯ 1:9.5 ◯ 1:10 ◯ 1:10 ◯ 1:11.2 1:11.21:13 1:13 : excellent/◯: good/: average/X: bad

As shown in TABLE 1, when the flow ratio of the SF₆:Cl₂ or SF₆:HCl was1:1 or more, or 1:4 or more, respectively, the afterimage wassignificantly improved. Since the bond dissociation energy of the Cl₂compared to HCl is small such that radicals or ions are easily emitted,the flow ratio of the Cl₂ is smaller than that of the HCl. However, whenthe flow ratio of the SF₆:Cl₂ or SF6:HCl was larger than 1:10, anetching characteristic was influenced.

According to an analysis result using secondary ion mass spectrometry(SIMS), a Cl atom amount remaining on channel areas of semiconductorsmeasured about 3.0 to 20 at %.

FIGS. 21 a and 21 b are graphs showing characteristic variations of TFTsbased on an amount of Cl supplied in detail. FIG. 21 a is a graphshowing a variation of drain current I_(d) based on a gate voltage V_(g)when the flow ratio of SF₆:HCl is 390 sccm:470 sccm, that is, 1:1, andFIG. 21 b is a graph showing a variation of drain current I_(d) based ona gate voltage V_(g) when the flow ratio of SF₆:HCl is 150 sccm:750sccm, that is, 1:5. The graph denoted by reference numeral A1 representsa case in which the drain current I_(d) is measured in a dark room andthe other graph, denoted by reference numeral B1, is a case in which thedrain current I_(d) is measured in a light room by irradiation of light.

As shown in the graphs, light leakage current in FIG. 21 a is largerthan that in FIG. 21 b. The light leakage current induces a voltage dropof the drain voltage, to incur the afterimages. Referring to FIGS. 15 to17 again, the remaining photoresist patterns 52 are removed. As shown inFIGS. 18 to 20, a passivation layer 180 is formed on the exposed gateinsulating layer 140, data lines 171 and drain electrodes 175, and theexposed projections 154 of the semiconductors 151.

Sequentially, the passivation layer 180 is removed by photograph etchingto form a plurality of contact holes 181, 182, 184, and 185. Finally, asshown in FIGS. 1 to 3, a transparent conducting material such ITO or IZOis formed on the passivation layer 180 by sputtering, and is patterned,to form pixel electrodes 191, contact assistants 81 and 82, andoverpasses 84.

According to the present invention, data lines are formed of amulti-layered structure including an Al film and a Mo film, and channelareas are formed using an etching gas of a predetermined flow ratio.Thereby, the characteristics of TFTs are improved and afterimageoccurrence decreases.

While this invention has been described in connection with what ispresently considered to be practical exemplary embodiments, it is to beunderstood that various modifications and equivalent arrangements willbe apparent to those skilled in the art and may be made without,however, departing from the spirit and scope of the invention.

1. A manufacturing method of a thin film transistor array panelcomprising: forming a gate line on a substrate; forming a gateinsulating layer, a semiconductor layer, and an ohmic contact on thegate line; forming a plurality of conducting films on the ohmic contact;forming a first photoresist pattern on the plurality of conductingfilms; etching the plurality of conducting films, the ohmic contact, andthe semiconductor layer using the first photoresist pattern as a mask;removing the first photoresist pattern by a predetermined thickness toform a second photoresist pattern; etching the plurality of conductingfilms using the second photoresist pattern as a mask to expose a portionof the ohmic contact; and etching the exposed ohmic contact using aCl-containing gas and a F-containing gas.
 2. The method of claim 1,wherein the flow ratio of the Cl-containing gas and the F-containing gasis 1:1 to 1:13.
 3. The method of claim 2, wherein the Cl-containing gasis at least one selected from Cl₂, HCl, CCl₄, BCl₃, and SiCl₂H₂.
 4. Themethod of claim 2, wherein the F-containing gas is SF₆ or CF₄.
 5. Themethod of claim 2, wherein the Cl-containing gas is HCl and a flow ratioof the HCl gas and the F-containing gas is 1:4 to 1:13.
 6. The method ofclaim 1, wherein the etching of the exposed ohmic contact is performedunder a pressure of 100 to 800 mT.
 7. The method of claim 1, wherein thefirst photoresist pattern comprises a first portion and a second portionhaving a thickness greater than that of the first portion.
 8. The methodof claim 7, wherein the formation of the second photoresist patterncomprises removing the second portion.
 9. The method of claim 1, whereinthe etching of the plurality of conducting films is performed by wetetching.
 10. The method of claim 1, wherein the plurality of conductingfilms comprise a first conducting film including Mo or Mo alloy and asecond conducting film including Al or Al alloy.
 11. The method of claim10, wherein the plurality of conducting films further comprise a thirdconducting films including Mo or Mo alloy.
 12. The method of claim 10,wherein the flow ratio of the Cl-containing gas and the F-containing gasis 1:1 to 1:13.
 13. The method of claim 12, wherein the Cl-containinggas is at least one selected from Cl₂, HCl, CCl₄, BCl₃, and SiCl₂H₂. 14.The method of claim 12, wherein the F-containing gas is SF₆ or CF₄. 15.The method of claim 12, wherein the Cl-containing gas is HCl and a flowratio of the HCl gas and the F-containing gas is 1:4 to 1:13.
 16. Themethod of claim 10, wherein the etching of the exposed ohmic contact isperformed under a pressure of 100 to 800 mT.
 17. The method of claim 10,wherein the first photoresist pattern comprises a first portion and asecond portion having a thickness greater than that of the firstportion.
 18. The method of claim 17, wherein the formation of the secondphotoresist pattern comprises removing the second portion.
 19. Themethod of claim 10, wherein the etching of the plurality of conductingfilms is performed by wet etching.